>I am using the ADXL05 myself, along with a 16C73 based system.
>I do not use the internal AtoD since 8 bits would be inadequate.
>I use the Motorola MC145051, a 10 bit serial device with 11 analog
>inputs. (There is a version with fewer inputs, can't remember the
>part number at the moment.)  Cost is less than $5.

Have you seen there new ADXL202? 2axis with PWM output (no a/d
needed). They have an evaluation board for under $30 and a serial out
version using a PIC 16C63! Source code is suppoded to be availible.